Invokana is an oral medication for type 2 diabetes that helps to lower blood glucose levels by encouraging the body to filter out more glucose from the blood and excrete it via the urine.
The drug helps patients to reduce blood sugars without increasing the likelihood of gaining weight as long as a healthy, balanced diet is followed and regular exercise taken.
Invokana is a relatively new drug and the effects on patients taking the drug for several years are not yet known.
- Trade name: Invokana
- Generic name: Canagliflozin
- Drug class: SGLT2 inhibitors
- Manufacturer: Janssen Pharmaceuticals
How does Invokana help in diabetes?
Invokana is effective in reducing blood glucose levels and has lowered blood glucose levels more significantly than DPP-4 inhibitors in clinical trials.
The antidiabetic drug causes the body to pass out glucose from the blood via the urine, which means that calories in the glucose are excreted. This action helps support weight loss when the drug is used in combination with a healthy diet and regular physical activity.
Invokana has also been shown to help lower blood pressure levels.
Mechanism of action
Invokana is in a class of drugs called sodium-glucose transport protein 2 (or SGLT2) inhibitors, which drugs work by increasing the amount of glucose that gets passed out in the urine.
When blood passes through the kidneys, the kidneys filter glucose out of the blood and the SGLT proteins then help reabsorb glucose back into the blood.
SGLT2 proteins are responsible for 90% of the glucose that is reabsorbed, so by blocking the action these proteins, less glucose is reabsorbed and so more glucose is excreted via the urine.
Who is canagliflozin suitable for?
Canagliflozin is suitable for adults with type 2 diabetes. Invokana was launched in the UK in February 2014 and is currently awaiting guidance from NICE as to whether the drug will be recommended for use on the NHS.
Who should not take Invokana?
Invokana tablets should not be used by:
- People with type 1 diabetes
- People with low kidney function
- People taking strong diuretic medication
How to take Invokana
Invokana is taken once daily with water and either with or without food.
Side effects of Invokana, that may be experienced, include:
- Hypoglycemia –if taken with sulphonylurea medication or insulin
- Hypotension (low blood pressure)
- Genital thrush
- Increased likelihood of urinary tract infections
- Increased need to visit the toilet (polyuria)
- Increases in LDL cholesterol
- Decrease in kidney function (a lowering of eGFR)
A complete list of side effects can be found in the patient information leaflet that comes with the medication.
Long term safety
Clinical trials have shown Invokana to be associated with a fall in aGFR (estimated glomerular filtration rate), a marker which indicates how well the kidneys are working. The fall in eGFR for patients taking Invokana indicates that there could be safety issues related to a drop in kidney function with the drug.
In the US, the FDA (Food and Drug Administration) have approved Invokana for use but it is important that health teams monitor kidney function regularly. Kidney health is of particular importance as people with diabetes have a much larger risk of suffering kidney damage (nephropathy).
There are questions about whether Invokana presents a risk to heart health. In one of the clinical trials, 13 patients taking canagliflozin suffered a major cardiovascular event (including heart attacks and strokes) within the first 30 days of taking the drug, compared with 1 patient taking a placebo. After more than a month, the number of cardiovascular events balanced out.
Invokana is a new drug and whilst it has gone through clinical tests, these cannot accurately predict the effects of long term safety over a number of years.